Limited options for meeting 2C warming target, warn climate experts

Nov 20, 2011

We will only achieve the target of limiting global warming to safe levels if carbon dioxide emissions begin to fall within the next two decades and eventually decrease to zero. That is the stark message from research by an international team of scientists, led by the University of Exeter, published today (20 November) in the journal Nature Climate Change.

The research focuses on the scale of reduction needed to keep future global warming at no more than two degrees Celsius over prior to the Industrial Revolution. This is now almost universally accepted as a safe limit.

The team examined the extent to which carbon emissions should be reduced, how steep this reduction needs to be and how soon we should begin. They used mathematical modelling techniques to construct a number of possible future scenarios, based on different assumptions on emissions reduction. They accounted for a likely range of climate sensitivities: the amount of warming for a given increase in .

The research shows how quickly emissions need to drop in the next few decades. It also highlights how remaining emissions could cause the two-degrees target to be exceeded in the long term, over the next few hundred years.

The researchers found that zero or negative emissions are compatible with this target if we reduce our by at least three per cent per year within the next two decades.

In a worst-case scenario of high climate sensitivity, we need to work towards negative emissions if we are to have a chance to keeping temperatures within the two-degrees target. This would mean using carbon-capture-and-storage technology combined with aggressive mitigation rates starting in the coming decade. The best-case scenario of low allows longer delays and more conservative mitigation rates, but still requires emissions to be eventually cut by at least 90%.

The results clearly show that if we delay reducing global emissions by just ten or twenty years we will then need to make much steeper reductions in order to meet a two-degrees warming target.

Lead author Professor Pierre Friedlingstein of the University of Exeter said: "When I analysed these results, I was surprised to see so few options available to us. We know we need to tackle global warming, but our research really emphasises the urgency of the situation. The only way for us to achieve a safe future climate will be to reduce emissions by at least three per cent, starting as soon as possible. The longer we leave it, the harder it will be."

Countries currently have different targets for carbon emission reductions. For example, the US proposes a 17 per cent reduction by 2020, the EU has set a target of a 20 to 30 per cent reduction by 2020 and Australia has an objective of a five to 25 per cent reduction by 2020, depending on other countries commitment.

"The good news is that it's not too late," said co-author Professor Susan Solomon of the University of Colorado. "The interesting news is that we really need to think in the very long-term as well as the near-term. Even a small amount of remaining emissions would eventually mean exceeding the target so we need to ensure that technologies are available to make our world carbon-free in the long run."

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omatumr
1.2 / 5 (20) Nov 20, 2011
We will only achieve the target of limiting global warming to safe levels if carbon dioxide emissions begin to fall within the next two decades and eventually decrease to zero.


Not true. The Sun control's Earth's climate [1,2].

World leaders do not understand and cannot control the energy source that powers the Sun [3,4].

1. "Super-fluidity in the solar interior: Implications for solar eruptions and climate", J Fusion Energy 21, 193-198 (2002
http://arxiv.org/.../0501441

2. "Earth's Heat Source - The Sun", Energy & Environment 20, 131-144 (2009)
http://arxiv.org/pdf/0905.0704

3. "Neutron Repulsion", The APEIRON Journal, in press (2011)
http://arxiv.org/...2.1499v1

4. "Climate change and national security"
http://judithcurr...t-140805

With kind regards,
Oliver K. Manuel
Former NASA Principal
Investigator for Apollo
http://myprofile....anuelo09
jsa09
3.8 / 5 (11) Nov 20, 2011
Granted that man contributes 1% - 2% of CO2 output into the atmosphere. It is over and above the natural sources and therefore cumulative. It is cumulative because the CO2 ppm has been increasing at an increasing rate since the industrial revolution. Increasing CO2 cannot be good even if it does not contribute to warming because it means a change in atmosphere at the very least.

We want to start looking towards clean air policies at the very least. And preventing our own waste from causing climate change could be a smart move. The way to move forward is to look at changing the industrial base.
axemaster
4.3 / 5 (16) Nov 20, 2011
I'll just come out and say it now. There is simply no chance that we will hit the 2C target. We will likely miss the 5C target as well.

The technology exists to put a stop to this right now, but we haven't yet. That's because we have non-scientist ignoramuses in control of the government.
StarGazer2011
1.6 / 5 (19) Nov 21, 2011
lucky everyone except the most easily deluded know its all a hoax by now, otherwise people might be worried.
omatumr
1.2 / 5 (17) Nov 21, 2011
I'll just come out and say it now . . . we have non-scientist ignoramuses in control of the government.


All of the slides and the surprisingly frank title of a new book in the last slide of a recent talk by solar physicist, Dr. Pal Brekke - "Our Explosive Sun" - may educate government scientists.

http://curry.eas....taFe.pdf

The word explosive describes the object that produced our elements, gave birth to the Solar System five billion years (5 Gyr) ago), sustains life, and exerts primary control over Earth's climate.

Reluctance to admit the Sun's explosive nature and repulsive forces between neutrons in the solar core have compromised astronomy, astrophysics, climatology, cosmology, nuclear, particle, solar and space sciences for the past four decades.

With kind regards,
Oliver K. Manuel
Former NASA Principal
Investigator for Apollo
http://myprofile....anuelo09
Ethelred
5 / 5 (11) Nov 21, 2011
Oliver recently made the mistake of actually posting a link to the Biblderberg Paper he rants about.

http://adsabs.har....3....5G

Now we know that Oliver didn't read it as it doesn't have any of the claims he makes about it. Its just a model of the photosphere and chromosphere that reached no definite conclusions, made no claim that the Sun is completely stable, has nothing to do with any global warming theory, and isn't part of the standard model he hates so much.

It is over 40 years old and had no computer modeling, no input from shady politicians, no Al Gore, no nothing that supports his bizarre attacks on it. Heck it doesn't even deal with the Sun's core in anyway and thus could have been written exactly the same way if they had used his self-contradicted Pulsar Sun silliness.

This is similar to the Kissinger letter he linked to. That too did not have the support he claimed was there.

Ethelred
Ethelred
5 / 5 (10) Nov 21, 2011
Oliver used to post a paper that claimed that CO2 is not a greenhouse gas. I showed it wrong just the rest of Oliver's crap.

He stopped posting it but he has never acknowledged that it was utter crap it truly was. He doesn't like answering questions.

The denialists would be better off without him. I wonder if Judith Curry cringes every time he posts on her site to promote his ridiculous theories such as his claim that the Sun has a RIGID iron mantle. He uses photos of PLASMA to prove this one.

Ethelred
ShotmanMaslo
3 / 5 (7) Nov 21, 2011
Unfortunately, even with these alarming predictions, the so called "green" movement will still continue to fight more against carbon-free nuclear energy, instead of the real threat - fossil power plants.
When was the last time they organised demonstrations and concerts against fossil power?
Green movement stopped being green long ago.
Ethelred
4.8 / 5 (10) Nov 21, 2011
I am afraid that the Japanese disaster has made it very unlikely that any nation besides France is going to start building a lot of fission plants. Which may be a bigger tragedy in the long run than the disaster itself.

Ethelred
Doom1974
4.3 / 5 (6) Nov 21, 2011
lucky everyone except the most easily deluded know its all a hoax by now, otherwise people might be worried.


I guess you know by experience
Pkunk_
1.4 / 5 (11) Nov 21, 2011
I'll just come out and say it now. There is simply no chance that we will hit the 2C target. We will likely miss the 5C target as well.

The technology exists to put a stop to this right now, but we haven't yet. That's because we have non-scientist ignoramuses in control of the government.


More like non-scientist ignoramuses have hijacked the IPCC and other meteorlogical institutes who refuse to account for the single biggest factor for global warming - The sun. They claim the Sun makes no difference ,but without the Sun we would have -250C as the mean temperature on Earth.

Piers Corbyn has a very solid model for why the world isn't "warming" and why our kids aren't going to see snow free winters as the University of East Anglia has systematically lied their way to everyone from the UN to the "greenies".
Vendicar_Decarian
1.2 / 5 (46) Nov 21, 2011
"Piers Corbyn has a very solid model for why the world isn't "warming"" - PhunkTard

And yet the Denialist Koch Brothers have just funded a study that shows that over the last decade the earth has warmed at a rate of .14'C per decade, which is about what the IPCC, NOAA, CRU, and the other research associations conclude.

So your claim that the earth isn't warming is.... A lie.

Now since your argument is based on a lie as it's primary assumption, we can just ignore everything else you have said.

Right?
Vendicar_Decarian
0.9 / 5 (43) Nov 21, 2011
"When was the last time they organised demonstrations and concerts against fossil power?" - ShotmanTard

Eleven Arrested at Coal Protest in Wise County Va.

http://www.coal-i...ounty-va

Stop Coal Protest, January 25th, BC Legislature

http://martlet.ca...slature/

coal protesters spared jail sentences

http://www.guardi...sentence

Chicago South East Side Coal Protest

http://www.youtub...Lb1h9t_w

2011 06 Raven Coal Protest

http://www.youtub...Wv0TlPT0

Need I go on?

Vendicar_Decarian
1 / 5 (44) Nov 21, 2011
If so then why is IR astronomy incapable of observing
in the same wavelengths that CO2 absorbs in?

As a self proclaimed "StarGazer" you should be able to answer that question.

Unless of course, you are lying about that as well.

"lucky everyone except the most easily deluded know its all a hoax by now" - StarGazer
Ethelred
5 / 5 (9) Nov 21, 2011
They claim the Sun makes no difference
Who is they? I know Oliver keeps telling a lie about like that but he does it to push his Iron Sun nonsense. Would you like to show where climatologist are unaware that the Sun exists and that it does vary. I noticed the Sun pretty early on in life and have know about the 22 years Solar cycle for more than 22 years. Funny thing to me is the way denialists make that claim and then out of the other side of their mouths they claim warming has stalled since 1998 while carefully forgetting to mention that the Sun started a KNOWN 11 year cooling cycle that went on for an extra 2 years at that.

Apparently for denialists the Sun only varies when they are claiming Climatologist are ignorant of it and they ignore it the rest of the time.

but without the Sun we would have -250C as the mean temperature on Earth.
I think most people have noticed that it gets cooler when the Sun goes down. So claiming people aren't aware of it is beyond silly.>>
Vendicar_Decarian
0.4 / 5 (38) Nov 21, 2011
"There is simply no chance that we will hit the 2C target. We will likely miss the 5C target as well." - AxeMaster

That would probably reduce the human population to under a half billion people since it guarantees a 10'C warming due to system inertia.

Vendicar_Decarian
0.6 / 5 (40) Nov 21, 2011
"The Sun exerts primary control over Earth's climate" - OmaTard

It does. It keeps the earth's surface at an average temperature of about 270'K

The Atmosphere increases that average by another 7 percent.

Poor Clueless OmaTard. You need more psychotherapy.
Ethelred
5 / 5 (8) Nov 21, 2011
Piers Corbyn has a very solid model for why the world isn't "warming"
Very nice. Now how does he deal with the fact that it is warming. Theories that fail to fit the evidence like that one need to be dumped or at least modified to fit the actual evidence.

University of East Anglia has systematically lied their way to everyone from the UN to the "greenies".
You got any evidence for that and why do you think East Anglia has total control of Science?

Ethelred
axemaster
2.3 / 5 (3) Nov 21, 2011
That would probably reduce the human population to under a half billion people since it guarantees a 10'C warming due to system inertia.

The sad thing is that something like that could ultimately end up happening, though personally I doubt to that extent. People don't realize that we are living in a golden age of climate stability, which is probably the main reason civilization started. Disrupting that stability is probably the surest way to bring it down again.
Vendicar_Decarian
0.5 / 5 (39) Nov 22, 2011
"That's because we have non-scientist ignoramuses in control of the government." - Yup

The American people deserve every ounce of the government they elect.
Ethelred
5 / 5 (2) Nov 24, 2011
Gee VD, Canada has non-scientists in control of government as well.

Lets see, the last time the US had a scientist as President was ummm NEVER and I bet the same for Canada's Prime Minister. The US has had some very bright people for President. And several idiots even if they did have above average IQs as Bush is supposed to have. The closest people to scientists were engineers. Two of those and maybe you could count Jefferson as a dabbler in science in an era when almost all scientists were dabblers.

The two I know of:

Jimmy Carter - who was better than he is credited for but still didn't do that well. The price of oil skyrocketed while he was in office and I don't see how he could have stopped that.

Herbert Hoover - who might have been a really good president IF the economy hadn't tanked the worst ever shortly after he got into office. Under those conditions his economic ideology was a rather bad fit.

Ethelred
Vendicar_Decarian
0.4 / 5 (37) Nov 26, 2011
Clearly he is at this point in a state of self imposed isolation using PhysOrg as a diversion while awaiting his conviction for decades of buggering his own children.

"Oliver used to post a paper that claimed that CO2 is not a greenhouse gas. I showed it wrong just the rest of Oliver's crap. He stopped posting it but he has never acknowledged that it was utter crap it truly was." - Ethelred
Vendicar_Decarian
0.2 / 5 (35) Nov 26, 2011
"And several idiots even if they did have above average IQs as Bush is supposed to have." - Ethel

Have you seen Bushie's teachers comments on the him? His claimed IQ was clearly purchased based on their assessments of him, as well as his performance while in office.

Most American's have not been told a lot of things about the Failure that was Bush. Including how he was stoned on Oxycontin during his first term and then switched to Ritalin in his second.

Didn't you ever wonder why his speech cleared up in his second term?

Ethelred
5 / 5 (2) Nov 27, 2011
Didn't you ever wonder why his speech cleared up in his second term?
It did? I never noticed.

Ethlered
Ethelred
5 / 5 (1) Nov 27, 2011
PhysOrg as a diversion while awaiting his conviction
That was years ago. He is on probation. For one conviction for attempted sodomy. The rest was past the time limits.

Ethelred